2005/11/29

Installing VMware Workstation on Ubuntu

When installing VMware on Ubuntu (and other Linux distros too, I think) from a compressed tar archive (for example, VMware-workstation-5.5.0-18463.tar.gz), make sure to change the directory to the root of an unpacked tarball, so you can start the installation by typing ./vmware-install.pl. Otherwise, the setup process will fail.

I had a problem installing VMware 5.5.0 and I found the solution here.

2005/11/27

Transaction isolation levels in Oracle Database

There's an interesting article about transaction isolation levels in the last issue (November/December 2005) of Oracle Magazine - On Transaction Isolation Levels by Tom Kyte.

Being a SQL Server guy who has to use NOLOCK all the time, I was surprised to learn that there is no READ UNCOMITTED isolation level in Oracle Database. And here's the explanation how it is solved:
When the query I'm executing gets to the block containing the locked row (row 342,023) at the bottom of the table, it will notice that the data in it has changed since execution began. To provide a consistent, or correct, answer, Oracle Database will create a copy of the block containing this row as it existed when the query began. That is, it will read a value of $100, which is the value that existed when the query began. Effectively, Oracle Database takes a detour around the modified data—it reads around it, reconstructing it from the undo (also known as a rollback) segment. A consistent and correct answer comes back without waiting for the transaction to commit.
Nice.

2005/11/23

Upgrading Ubuntu 5.04 to 5.10 (in, increasingly inaccurately named, 3 easy steps)

All you have to do to upgrade Ubuntu 5.04 (Hoary Hedgehog) to 5.10 (Breezy Badger) is:
  1. Start Synaptic Package Manager.
  2. Go to Settings / Repositories.
  3. Change Distribution from hoary to breezy for every Ubuntu repository (example).
  4. Close the Repositories window; the package information will be automatically reloaded.
  5. Press Mark All Upgrades button and choose Smart Update.
That's all - Synaptic Package Manager will download all the needed packages and install them.

2005/11/01

VS 2005 Beta 2 - cannot create a new project or open an existing one

I have been using Visual Studio 2005 Beta 2005 for a few weeks and one day, completely out of the blue it failed to open my project. I tried to open another one - the same result. I also couldn't create a new project.

Unfortunately, I didn't jot down the error message, but I remember it mentioned Microsoft.Common.targets file.

I checked this file on my machine and it turned out that it was empty. I did some googling to make sure that it is not normal and then reinstalled .NET Framework 2.0 (use repair option) - it helped!